Percutaneous interventional technology is a rapidly developed means of disease treatment in recent years, and its application range is becoming wider and wider. A variety of materials, devices and drugs can be placed into heart, artery and vein blood vessels of a human body by using catheter interventional therapy, wherein the devices may be heart defect occluders, vascular plugs, vascular filters, etc.
The transcatheter interventional occluder is a commonly used device in transcatheter interventional therapy and can be used for the minimally invasive treatment of such congenital heart diseases as atrial septal defects and ventricular septal defects, patent ductus arteriosus and patent foramen ovale. An occluder in the prior art typically comprises an occlusion body having two occlusion units, for covering the tissue of the two sidewalls of the defect site. However, at present, the occlusion unit is, more often than not, prepared from shape memory metals or polymer materials. The shape memory metals may cause fatigue failure in use, while the polymer materials have the characteristics of low elasticity or inelasticity, which will lead to insufficient contraction force between the two occlusion units as well as the inability of fitting either side of the defect site, thereby affecting the occluding effect. Therefore, the occluder needs an effective restraining structure to keep the distance between the two occlusion units (namely, the waist height of the occluder) stable to ensure the reliability of the occlusion.